Intestinal strongyloidiasis in Vietnam: Can lead to encephalitis, pneumonia and lead to high mortality? What are the causes and symptoms of the disease?
What is Intestinal strongyloidiasis in Vietnam? Where does the disease come from? How is it transmitted?
Based on Decision 1384/QD-BYT in 2022 provides guidelines for the diagnosis, treatment and prevention of Intestinal strongyloidiasis in Vietnam as follows:
Intestinal strongyloidiasis (Strongyloidiasis) is common in tropical and subtropical regions, with approximately 30-100 million people are infected. Humans are infected by strongyloidiasis larvae that penetrate through the skin and enter the body through contact with contaminated soil. In addition, people can be infected through self-infection because female strongyloides lay eggs, which then develop into larvae or lay larvae and adult worms right in the intestine. Common in immunocompromised people. The disease manifests with digestive, respiratory, neurological symptoms..., in case of severe infection, the patient can die.
- Pathogens
The most common causative agent of intestinal strongyloidiasis is Strongyloides stercoralis, in addition, there is a species of Strongyloides fuelleborni, which often causes disease in monkeys, apes, dogs but sometimes causes disease in humans.
- Source of strongyloidiasis
Human is the main host, in addition, it may be present in some other animals such as monkeys, apes, dogs...
- Mode of transmission
+ By skin route: Strongyloidiasis larvae penetrate through the skin mucosa into the body.
+ Self-infection: Because the female worm lays eggs, the eggs hatch into larvae or lay larvae and develop into adult worms right in the intestines, causing disease in humans.
- Susceptibility and immunity
+ Everyone is at risk of infection when they have contact with soil and sand with strongyloid larvae.
+ Immunity to strongyloides is the highest among soil-borne worms, but there is no long-term immunity, so it is easy to re-infect.
- The development cycle of strongyloides
+ The strongyloidy cycle includes: parasitic cycle and free cycle.
The development cycle of strongyloides:
(1) Strongyloidiasis larvae with bulging esophagus (L1) are released into the environment by the feces of an infected person.
(2) In the environment, larvae with a bulbous esophagus can develop into free-living adult worms or become larvae with a thread-shaped esophagus (L3- the larval stage capable of infecting ) penetrates human skin (6).
(3) Adult worms mate, and the female lays eggs.
(4) Eggs hatch into larvae with bulging esophagus outside the environment.
(5) These larvae may develop into free-living adults (2) or develop infective tube-esophageal (L3) larvae (6).
(6) Larvae with a tubular esophagus (L3) penetrate from the soil through exposed skin.
(7) The larvae travel through the bloodstream to the lungs, through the pulmonary capillaries, to the bronchial tree to the pharynx, are swallowed down the gastrointestinal tract, and then to the small intestine, where they mature.
(8) In the small intestine, the adult female worm lays eggs.
(9) Eggs hatch into larvae with bulging esophagus. Most larvae are excreted in the feces.
(10) Some larvae with a bulbous esophagus (L1) in the large intestine develop into larvae with a tubular esophagus, penetrating through the intestinal mucosa (internal autoinfection) or the perianal skin (spontaneously). external infection) and move freely to other organs according to the normal cycle of infection.
What are the clinical symptoms ofIntestinal strongyloidiasis in Vietnam?
Based on Decision 1384/QD-BYT in 2022 prescribes the clinical symptoms of Intestinal strongyloidiasis in Vietnam as follows:
a) Common disease form Common
symptoms:
- Digestive disorders: diarrhea is the most common symptom. , which may persist for more than 2 weeks and alternate with episodes of constipation.
- Abdominal pain: usually pain in the epigastrium, right lower quadrant accompanied by nausea and vomiting.
- Allergies: itching, red rash at the site of penetration through the skin or maculopapular rash, urticaria, scattered throughout the body.
In addition, there may be symptoms such as: fatigue, anorexia, weight loss, anemia, enteritis, duodenal ulcer, colon, gastrointestinal bleeding, arthritis, arrhythmia, kidney syndrome cough and bronchial asthma/cough.
b) Severe form
- Severe disease including strongyloidiasis syndrome and disseminated strongyloidiasis is common in immunocompromised patients, prolonged corticosteroid or immunosuppressive drug use and is often accompanied by other symptoms. other diseases such as: bacterial infection, chronic obstructive pulmonary disease, chronic kidney failure, malignancy, diabetes, malnutrition.
- Disseminated strongyloidiasis infects many organs such as lungs, liver, heart, kidneys, endocrine organs and central nervous system. The disease is often severe and leads to high mortality.
- Strongyloidiasis larvae cause enteritis, gastrointestinal bleeding or intestinal perforation leading to peritonitis.
- Neurological: The patient is easily excitable, neurasthenic, may have encephalitis - meningoencephalitis, brain abscess, epilepsy, impaired consciousness.
- Ectopic strongyloides can cause symptoms of pneumonia, lung abscess, bronchial asthma, interstitial pneumonia, parenchymal hemorrhage, hemorrhagic spots in the alveoli, respiratory failure.
- Strongyloidiasis larvae cause lymphadenopathy, endocarditis, pancreatitis, liver failure, kidney failure, arthralgia, arthritis, myalgia, generalized edema.
c) Subclinical
- Laboratory tests
+ Fecal examination by methods: fresh endoscopy, or Baermann method
+ Testing duodenal fluid, bronchial lavage or sputum: finding strongyloidiasis larvae.
+ ELISA test: detecting antibodies against strongyloides stercoralis in serum is of great diagnostic value.
+ Total IgE test: may be increased.
+ Complete blood count: eosinophil count is usually increased, the number of white blood cells in the peripheral blood may be increased.
Blood biochemistry: may increase liver enzymes.
+ Molecular biology test: identify strongyloides species.
d) Diagnostic imaging
+ Abdominal ultrasound: there is thick wall of small bowel loops, regular thickness.
+ Chest X-ray: may show interstitial infiltration, consolidation, or abscess.
+ CT scan, MRI: when there is nerve damage.
Intestinal strongyloidiasis in Vietnam: Can lead to encephalitis, pneumonia and lead to high mortality? What are the causes and symptoms of the disease?
How is intestinal strongyloidiasis diagnosed?
Based on Decision 1384/QD-BYT in 2022 prescribes the diagnosis of Intestinal strongyloidiasis in Vietnam as follows:
- Suspicious case
+ Epidemiological factors: Patient has a history of direct contact with soil or lives in endemic areas.
+ The patient has clinical signs pointing towards strongyloidiasis.
- Case of confirmed disease: A case of suspected disease and one of the following two tests:
+ Stool test finds strongyloidiasis larvae in stool, duodenal fluid, in bronchial lavage fluid or sputum or
+ Test Antibody ELISA: positive.
- Differential diagnosis
+ Peptic ulcer: the patient has a history of gastritis, based on the results of gastroscopy to confirm the diagnosis.
+ Differential diagnosis with hookworm larvae: by morphology.
+ gnathostomiasis: lesions are large and small irregular lumps that move and itch. ELISA test against gnathostomiasis: positive.
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